The invention provides a traditional Chinese medicinal composition for effectively treating diabetes. The traditional Chinese medicinal composition is prepared through using Trichosanthis Radix, gypsum, Radix Pseudostellariae, Rhizoma Alismatis, Chinese magnoliavine, Rhizoma Coptidis, wolfberry fruit, Radix Platycodonis, mantis egg-case, Salvia miltiorrhiza, white peony root, Radix Scrophulariae, Euonymus alatus, Radix Puerariae, prepared rehmannia root, licorice, Chinese yam, Rhizoma Anemarrhenae, Ramulus Mori, Rhizoma Atractylodis Macrocephalae, Cortex Moutan, Achyranthes bidentata, Poria cocos, Rheum officinale, cinnamon, Radix Scutellariae and haw. The traditional Chinese medicinal composition is prepared through treating Chinese traditional herbal medicines as raw materials, utilizing a scientific formula, passes the repeated validation of clinical tests, and accords with the theory of the traditional Chinese medical science. The traditional Chinese medicinal composition can cure the diabetes and effectively prevent the generation of the diabetes from changing the physical quality of diabetes patients, and can avoid populations especially having a family diabetes history from suffering the diabetes through in-advance administration and early-stage prevention. The traditional Chinese medicinal composition has the advantages of high treatment efficiency, low cost, short time, and no toxic side effects.